If Statement

Each part of the if statement must be a single statement.
If we want to execute more than one statement then we must combine them into a single block statement using curly brackets.
In C# the parentheses around the condition to be tested is compulsory.

If

if (bValue == true) 
{ 
   sVariable1 = "text"; 
} 

You can put this on one line, but this makes it much harder to read.

if (bValue == true) sVariable1 = "text"; 
if (bValue == true) { sVariable1 = "text"; } 

Or you can put this on two lines.

if (bValue == true) 
{ sVariable1 = "text"; } 

If - Else

if (bValue == true) 
{ 
   sVariable1 = "text"; 
} 
else 
{ 
   sVariable2 = "text"; 
} 

You could put this on 4 lines

if (bValue == true) 
{ sVariable1 = "text"; } 
else 
{ sVariable2 = "text"; } 

Or you can use the Conditional Operator

if (bValue == true) ? sVariable1 = "text" sVariable2 = "text"; 

If - ElseIf - Else

Very important to remember that "else if" is 2 words in C#.

if (iValue < 10) 
{ 
} 
else if (iValue < 20) 
{ 
} 
else 
{ 
} 

If (OR)

if ( ( a > b ) | ( c < d ) ) 
{ 
} 

If (OR conditional)

You can use the "OrElse" if you do not want the second expression evaluated when the first expression is not true

if ( ( a > b ) || ( c < d ) ) 
{ 
} 

If (AND)

if ( ( a > b ) & ( c < d ) ) 
{ 
} 

If (AND conditional)

You can use the "OrElse" if you do not want the second expression evaluated when the first expression is not true

if ( ( a > b ) && ( c < d ) ) 
{ 
} 

If Nested

if (bValue === false) 
{ 
   if (iValue < 10) 
   { 
   } 
} 

Continue

This can be used inside an if statement, when it is inside a loop.
The continue statement breaks one iteration (in the loop), if a specified condition occurs, and continues with the next iteration in the loop.

Break

This can be used inside an if statement, when it is inside a loop.
The break statement can also be used to jump out of a loop.